Traffic and Granular Flow ’07

pp 413-419

Modelling and Simulating Several Time-Delay Mechanisms in Human and Automated Driving

  • Martin TreiberAffiliated withInstitute for Transport & Economics, Technische Universität Dresden
  • , Arne KestingAffiliated withInstitute for Transport & Economics, Technische Universität Dresden

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In vehicular traffic, reactions to new traffic situations are subject to several mechanisms of time delay. Besides the reaction time of the drivers (or sensors), the finite acceleration capabilities lead to a nonzero “velocity adaptation time” to perform the action itself (e.g. changing the velocity). The commonly used explicit integration schemes for simulating the models introduce the update time as a third delay parameter. By means of numerical simulations with a time-continuous car-following model, we investigate how these times interplay with each other. We show that the three delay times give rise to two types of instabilities: The long-wavelength string instability is mainly driven by the velocity adaptation time while short-wavelength local instabilities arise for sufficiently high reaction and update times. We show that, with respect to stability, there is an ‘optimal’ adaptation time as a function of the reaction time and draw implications for human vs. semi-automated driving.